Question

he safety director of a large steel mill took samples at random from company records of...

he safety director of a large steel mill took samples at random from company records of minor work-related accidents and classified them according to the time the accident took place.

Number of Number of
Time Accidents Time Accidents
8 up to 9 a.m. 10 1 up to 2 p.m. 6
9 up to 10 a.m. 6 2 up to 3 p.m. 8
10 up to 11 a.m. 6 3 up to 4 p.m. 7
11 up to 12 p.m. 16 4 up to 5 p.m. 20

Using the goodness-of-fit test and the 0.01 level of significance, determine whether the accidents are evenly distributed throughout the day.

H0: The accidents are evenly distributed throughout the day.   
H1: The accidents are not evenly distributed throughout the day.

a) State the decision rule, using the 0.01 significance level.

b) Compute the value of chi-square.

c)What is your decision regarding H0?

Homework Answers

Answer #1


A)The significance level for a given hypothesis test is a value for which a P-value less than or equal to is considered statistically significant. If the p value is 0.01 is considered significant or insignificant for confidence interval of 0.99.

B)
observed frequencies of accidents (fo)=10,6,6,16,6,8,7,20

Total of accidents are: 10+6+6+19+6+8+7+20=79

Average = 79/8

expected frequencies (fe)= 79/8,79/8,79/8,/79/8,79/8,79/8,79/8,79/8

H0: Accidents are evenly distributed throughout the day
H1: Accidents are not evenly distributed throughout the day

chi-square test -statistic =sum(fo-fe)^2/fe = 20.09

Critical value = chi-inv(0.01,7)= 18.475

C)
Since the test statistic does fall inside the rejection region, we do reject H0.
Using a 0.01 level of significance there is sufficient evidence to conclude that
the accidents are not evenly distributed throughout the day.

Know the answer?
Your Answer:

Post as a guest

Your Name:

What's your source?

Earn Coins

Coins can be redeemed for fabulous gifts.

Not the answer you're looking for?
Ask your own homework help question
Similar Questions
The safety director of large steel mill took samples at random from company records of minor...
The safety director of large steel mill took samples at random from company records of minor work-related accidents and classified them according to the time the accident took place. Number of Number of Time Accidents Time Accidents 8 up to 9 a.m. 5 1 up to 2 p.m. 6 9 up to 10 a.m. 10 2 up to 3 p.m. 9 10 up to 11 a.m. 8 3 up to 4 p.m. 9 11 up to 12 p.m. 18 4...
The safety director of a large steel mill took samples at random from company records of...
The safety director of a large steel mill took samples at random from company records of minor work-related accidents and classified them according to the time the accident took place. Number of Number of Time Accidents Time Accidents 8 up to 9 a.m. 8 1 up to 2 p.m. 8 9 up to 10 a.m. 4 2 up to 3 p.m. 10 10 up to 11 a.m. 8 3 up to 4 p.m. 9 11 up to 12 p.m. 11...
A particular report included the following table classifying 712 fatal bicycle accidents according to time of...
A particular report included the following table classifying 712 fatal bicycle accidents according to time of day the accident occurred. Time of Day Number of Accidents Midnight to 3 a.m. 38 3 a.m. to 6 a.m. 27 6 a.m. to 9 a.m. 66 9 a.m. to Noon 77 Noon to 3 p.m. 98 3 p.m. to 6 p.m. 127 6 p.m. to 9 p.m. 164 9 p.m. to Midnight 115 (a) Assume it is reasonable to regard the 712 bicycle...
A particular report included the following table classifying 818 fatal bicycle accidents that occurred in a...
A particular report included the following table classifying 818 fatal bicycle accidents that occurred in a certain year according to the time of day the accident occurred. Time of Day Number of Accidents midnight to 3 a.m. 47 3 a.m. to 6 a.m. 52 6 a.m. to 9 a.m. 84 9 a.m. to noon 72 noon to 3 p.m. 79 3 p.m. to 6 p.m. 157 6 p.m. to 9 p.m. 193 9 p.m. to midnight 134 For purposes of...
An engineer wants to determine the effectiveness of a safety program. He collects annual loss of...
An engineer wants to determine the effectiveness of a safety program. He collects annual loss of hours due to accidents in 12 plants before and after the program was put into operation. Plant Before After Plant Before After 1 102 88 7 94 106 2 108 102 8 81 88 3 101 97 9 77 76 4 96 105 10 58 59 5 99 81 11 95 62 6 81 82 12 104 102 Click here for the Excel Data...
Ninety five cities provided information on vacancy rates (in percent) in local apartments in the following...
Ninety five cities provided information on vacancy rates (in percent) in local apartments in the following frequency distribution. The sample mean and the sample standard deviation are 10% and 4.0%, respectively. (You may find it useful to reference the appropriate table: chi-square table or F table) Vacancy Rate   Frequency Less than 6      11      6 up to 9      24      9 up to 12      38      12 or more      22      a. Apply the goodness-of-fit test...
Perform the following tests answering each part. Assume random samples taken from populations that are normally...
Perform the following tests answering each part. Assume random samples taken from populations that are normally distributed. The health of employees is monitored by weighing them. A sample of 54 employees has a mean weight of 185 lb and σ is known to be 26.2 lb, use a 0.10 sig. level to test the claim that the population mean of employees weights is less than 200 lb. 1.---What is the Claim in symbolic Format? 2.---What is the Rest in symbolic...
Bardi Trucking Co., located in Cleveland, Ohio, makes deliveries in the Great Lakes region, the Southeast,...
Bardi Trucking Co., located in Cleveland, Ohio, makes deliveries in the Great Lakes region, the Southeast, and the Northeast. Jim Bardi, the president, is studying the relationship between the distance a shipment must travel and the length of time, in days, it takes the shipment to arrive at its destination. To investigate, Mr. Bardi selected a random sample of 20 shipments made last month. Shipping distance is the independent variable and shipping time is the dependent variable. The results are...
According to the Energy Information Administration (official energy statistics from the U.S. government), the mean price...
According to the Energy Information Administration (official energy statistics from the U.S. government), the mean price for one gallon of unleaded regular gasoline in U.S. cities for August, 2011 was $3.64. A random sample of 30 pumps in cities in the state of Georgia yielded an average price of $3.16 per gallon for unleaded gasoline. Assume that σ = $0.90. Test whether the population mean price for unleaded gasoline is lower in Georgia than the general population, using a significance...
The following observations are obtained from a random sample of 10 individuals: Individual x y 1...
The following observations are obtained from a random sample of 10 individuals: Individual x y 1 9.08 5.25 2 4.23 3.58 3 6.88 4.75 4 10.3 5.38 5 8.09 4.27 6 10.6 5.79 7 4.50 3.41 8 8.32 5.75 9 7.17 4.74 10 9.45 5.43 Run a t-linear regression test on this data. (HINT: make sure you copy the numbers correctly!) What are the appropriate null and alternative hypotheses? H0:r=0H1:r≠0 H0:ρ=0H1:ρ<0 H0:ρ=0H1:ρ≠0 H0:r=0H1:r>0 H0:r=0H1:r<0 H0:ρ=0H1:ρ>0 What is the correlation coefficient?...